#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

ll n;

int main() {
    cin >> n;
    ll res = 0;
    for (ll a = 1; a*a*a <= n; a++) 
        for (ll b = a; a*b*b <= n; b++)
            res += n/a/b-b+1;
    
    cout << res << endl;
    return 0;
}